title: Peroxisomal beta-oxidation of polyunsaturated fatty acids in Saccharomyces cerevisiae: isocitrate dehydrogenase provides NADPH for reduction of double bonds at even positions.
abstract: The beta-oxidation of saturated fatty acids in Saccharomyces cerevisiae is confined exclusively to the peroxisomal compartment of the cell. Processing of mono- and polyunsaturated fatty acids with the double bond at an even position requires, in addition to the basic beta-oxidation machinery, the contribution of the NADPH-dependent enzyme 2,4-dienoyl-CoA reductase. Here we show by biochemical cell fractionation studies that this enzyme is a typical constituent of peroxisomes. As a consequence, the beta-oxidation of mono- and polyunsaturated fatty acids with double bonds at even positions requires stoichiometric amounts of intraperoxisomal NADPH. We suggest that NADP-dependent isocitrate dehydrogenase isoenzymes function in an NADP redox shuttle across the peroxisomal membrane to keep intraperoxisomal NADP reduced. This is based on the finding of a third NADP-dependent isocitrate dehydrogenase isoenzyme, Idp3p, next to the already known mitochondrial and cytosolic isoenzymes, which turned out to be present in the peroxisomal matrix. Our proposal is strongly supported by the observation that peroxisomal Idp3p is essential for growth on the unsaturated fatty acids arachidonic, linoleic and petroselinic acid, which require 2, 4-dienoyl-CoA reductase activity. On the other hand, growth on oleate which does not require 2,4-dienoyl-CoA reductase, and NADPH is completely normal in Deltaidp3 cells.
authors.affiliation: Department of Clinical Chemistry, University of Amsterdam, Academic Medical Centre, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.
authors.forename: C W
authors.initials: CW
authors.lastname: van Roermund
authors.forename: E H
authors.initials: EH
authors.lastname: Hettema
authors.forename: A J
authors.initials: AJ
authors.lastname: Kal
authors.forename: M
authors.initials: M
authors.lastname: van den Berg
authors.forename: H F
authors.initials: HF
authors.lastname: Tabak
authors.forename: R J
authors.initials: RJ
authors.lastname: Wanders
mesh_terms: D000595:Amino Acid Sequence; D016718:Arachidonic Acid / Q000494:pharmacology; D002244:Carbon / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003600:Cytosol / Q000201:enzymology; D044943:Fatty Acid Desaturases / Q000032:analysis / Q000187:drug effects; D005227:Fatty Acids / Q000494:pharmacology; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics / Q000502:physiology; D006860:Hydrogen Bonding; D007521:Isocitrate Dehydrogenase / Q000378:metabolism; D007536:Isomerism; D019787:Linoleic Acid / Q000494:pharmacology; D008830:Microbodies / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D008928:Mitochondria / Q000201:enzymology; D009249:NADP / Q000378:metabolism / Q000494:pharmacology; D019301:Oleic Acid / Q000494:pharmacology; D009829:Oleic Acids / Q000494:pharmacology; D010084:Oxidation-Reduction; D044925:Oxidoreductases Acting on CH-CH Group Donors; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity / Q000187:drug effects
chemical_list: D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D009829:Oleic Acids; D000074435:Peroxisome-Targeting Signal 1 Receptor; D018160:Receptors, Cytoplasmic and Nuclear; D016718:Arachidonic Acid; D019301:Oleic Acid; C008820:petroselinic acid; D009249:NADP; D002244:Carbon; D019787:Linoleic Acid; D007521:Isocitrate Dehydrogenase; C039355:isocitrate dehydrogenase (NADP+); D044943:Fatty Acid Desaturases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C100153:2,4-dienoyl-CoA reductase